Unlocking 5140i

Hello,

During a recent visit to France, my mobile phone was stolen, and I
bought a Nokia 5140i linked to SFR.
I am back in Australia and want to use a local telco but cannot get
any one to unlock the phone.
I have phoned and messaged SFR many times and they will not help.

Does anyone know a place local to Sydney who will unlock it or is
there any software that would do the job.

If not, as its Christmas, anyone want a 5140i :-)